JP7272066B2 - Biofilm formation suppressing coating agent and biofilm formation suppressing laminate - Google Patents

Description

TECHNICAL FIELD The present invention relates to a biofilm formation-inhibiting laminate having a biofilm formation-inhibiting coating agent and a coating film comprising the coating agent.

Biofilms, also known as biofilms or slimes, are generally water-based microbes such as bacteria and fungi that adhere to and proliferate on the surface of substances. Refers to what is formed. Comparing before and after biofilm formation, once a biofilm is formed, it exhibits significantly higher resistance to cleaning/removal, antibiotics, drugs, heat, drying, and the like. As a result, hazards caused by attached and proliferated microorganisms occur, causing problems in various industrial fields.

For example, when bacteria adhere to the inside of a tube of a medical device such as a catheter and form a biofilm, it causes clogging, making it impossible to administer treatment. Biofilms can also slough off and bacterial aggregates can enter the body and cause serious illness. When a biofilm is formed in the pipes of a food plant, the biofilm peels off, which not only leads to contamination of products, but also causes food poisoning due to toxins derived from microorganisms. Furthermore, biofilm formation on metal surfaces causes metal corrosion and accelerates aging of facilities. In addition, the formation of a biofilm on the inner surface of an aquarium adversely affects organisms in the aquarium.

In this way, suppression of biofilm formation is required, and various methods are being investigated.

Patent Document 1 discloses a biofilm treatment agent containing a low-molecular-weight amine oxide surfactant in a biofilm-disintegrating agent containing an alkali inorganic salt as a main component. Techniques for cleaning with active agents are disclosed. However, it is difficult to peel off the biofilm once formed, and the labor burden due to cleaning work is large. In addition, since a large amount of water is used during the cleaning work, there are problems of disposal and environmental pollution.

In Patent Document 2, a polymer compound derived from a vinyl-based monomer having one or more groups selected from an amino group and a quaternary ammonium group and having an anionic group is used to suppress the formation of a biofilm. A method for preventing the adhesion of microorganisms, a sterilizing effect, and an antibacterial effect are exhibited by the polymer compound, and a method for suppressing biofilm formation is disclosed. However, the polymer compound has poor water resistance and insufficient biofilm formation inhibitory properties.

Patent Document 3 discloses an amphoteric urethane resin obtained by subjecting a phosphorylcholine group-containing diol compound to addition condensation thereof, and is disclosed to be excellent in biocompatibility. However, it has a rigid structure, poor adhesion and conformability to some substrates, and poor solubility in solvents, so it has problems in terms of handling.

JP 2008-156389 A JP 2010-163429 A JP 2011-162522 A

An object of the present invention is to provide a coating film comprising a biofilm formation suppressing coating agent and the coating agent, which is excellent in safety, coatability and water resistance, and enables long-term suppression of biofilm formation. An object of the present invention is to provide a film formation-suppressing laminate.

The present invention relates to the following <1> to <6> biofilm formation inhibiting coating agents and <7> biofilm formation inhibiting laminate.

<1> A biofilm formation-inhibiting coating agent comprising a urethane-based polymer (a) containing an amine oxide group and having a mass average molecular weight of 10,000 to 10,000,000.

<2> Urethane-based polymer (a), biofilm formation inhibitor coating agent according to <1> containing 0.25 ~ 5 mmol / g of amine oxide groups.

<3> The urethane-based polymer (a) is a reaction product of a urethane-based polymer having a tertiary amino group and an oxidizing agent, or is obtained by polymerizing a diol compound having an amine oxide group and a polyisocyanate. The biofilm formation suppressing coating agent according to <1> or <2>, which is a polymer.

（式中、
Ｒ^１、Ｒ^３ _、Ｒ^６はそれぞれ独立して炭素数１～６のアルキレン基を、
Ｒ^２、Ｒ^４、Ｒ^５、Ｒ^７、Ｒ^８はアルキル基、アリール基、アラルキル基、ピリジル基を、
ＹはＯまたはＮＨを表し、
＊＊はウレタン系ポリマーの主鎖との結合位置を表す。） <4> The urethane-based polymer (a), <1> to <3> having at least one structure represented by the following general formulas 1 to 3, the biofilm formation suppressing coating agent according to any one of items.

(In the formula,
R ¹ , R ³ _and R ⁶ each independently represent an alkylene group having 1 to 6 carbon atoms,
R ² , R ⁴ , R ⁵ , R ⁷ and R ⁸ are an alkyl group, an aryl group, an aralkyl group and a pyridyl group;
Y represents O or NH,
** represents the bonding position with the main chain of the urethane-based polymer. )

<5> The biofilm formation suppressing coating agent according to any one of <1> to <4> further comprising a cross-linking agent.

<6> A biofilm formation suppression laminate having a coating film made of the biofilm formation suppression coating agent according to any one of <1> to <5> on a substrate.

INDUSTRIAL APPLICABILITY According to the present invention, it is possible to provide a biofilm formation-inhibiting coating agent that is excellent in safety, coatability, and water resistance, and that enables long-term biofilm formation inhibition.
The biofilm formation-inhibiting coating agent of the present invention can be suitably used on the surfaces of substances on which microorganisms are expected to adhere and form biofilms, such as medical equipment, manufacturing equipment, or the inner surface of water tanks.

The biofilm formation-inhibiting coating agent of the present invention is characterized by comprising a urethane-based polymer (a) containing an amine oxide group and having a mass average molecular weight of 10,000 to 10,000,000. By being a polymer containing an amine oxide group, not only excellent safety, coatability and water resistance, but also long-term biofilm formation inhibitory effect can be maintained.

<Biofilm formation suppression coating agent>
<Urethane polymer (a)>
The urethane-based polymer (a) of the present invention contains an amine oxide group and has a weight average molecular weight of 10,000 to 10,000,000, and conventionally known polymers can be used. may be used together. Specifically, it preferably includes structures represented by the following general formulas (1), (2), and (3).

（式中、
Ｒ^１、Ｒ^３ _、Ｒ^６はそれぞれ独立して炭素数１～６のアルキレン基を、
Ｒ^２、Ｒ^４、Ｒ^５、Ｒ^７、Ｒ^８はアルキル基、アリール基、アラルキル基、ピリジル基を、
ＹはＯまたはＮＨを表し、
＊＊はウレタン系ポリマーの主鎖との結合位置を表す。）

(In the formula,
R ¹ , R ³ _and R ⁶ each independently represent an alkylene group having 1 to 6 carbon atoms,
R ² , R ⁴ , R ⁵ , R ⁷ and R ⁸ are an alkyl group, an aryl group, an aralkyl group and a pyridyl group;
Y represents O or NH,
** represents the bonding position with the main chain of the urethane-based polymer. )

The urethane-based polymer (a) in the present invention comprises a polyol component, a polyisocyanate component, and a monomer that serves as an introduction source of amine oxide groups as essential components, and if necessary, a polyamine component, a monofunctional hydroxyl group component, and a monofunctional is the reaction product with the amine component of Examples of the monomer that serves as the introduction source of the amine oxide group include a monomer having an amine oxide group and a monomer having a tertiary amino group that serves as a precursor thereof.

Moreover, the urethane-based polymer (a) in the present invention can be obtained by the following two methods. That is, a diol compound having an amine oxide group and a polyisocyanate can be polymerized to obtain a urethane-based polymer (a) having an amine oxide group.
Alternatively, after obtaining a urethane-based polymer having a tertiary amino group, the tertiary amino group can be reacted with an oxidizing agent to introduce an amine oxide group into the polymer. The latter method is preferred in that side reactions are less likely to occur. The reaction of the tertiary amino group with an oxidizing agent is hereinafter also referred to as "oxidation".

[Tertiary amino group-containing monomer]
Examples of tertiary amino group-containing monomers as precursors before oxidation include tertiary amino group-containing diols having 1 to 20 carbon atoms. Examples include N-alkyldialkanolamine and N,N-dialkylmonoalkanolamine.
N-alkyldialkanolamines include, for example, N-methyldiethanolamine, N-ethyldiethanolamine, N-propyldiethanolamine, N-butyldiethanolamine and N-methyldipropanolamine.
N,N-dialkylmonoalkanolamines include, for example, N,N-dimethylethanolamine.
In addition, N,N-bis(2-hydroxyethyl)benzylamine, N,N-bis(2-hydroxyethyl)cyclohexylamine, diethanol-p-toluidine, diisopropanol-p-toluidine, N,N-bis(2 -hydroxyethyl)aniline, N,N-bis(2-hydroxypropyl)aniline, N,N-bis(2-hydroxyethyl)-3-chloroaniline, N,N-bis(2-hydroxyethyl)-4- pyridine carboxamide, N,N-bis(2-hydroxyethyl)-α-aminopyridine, 1,4-bis(2-hydroxyethyl)piperazine, 3-diethylaminopropane-1,2-diol, 3-dimethylaminopropane -1,2-diols and the like are mentioned as tertiary amino group-containing monomers.

[Polyol component]
The polyol component is not particularly limited, but may be ethylene glycol, 1,4-butanediol, neopentyl glycol, butylethylpentanediol, glycerin, trimethylolpropane, glycols such as pentaerythritol, polyester polyol, polyether. Examples include polyols, polyester polyols, polybutadiene polyols, hydrogenated polybutadiene polyols, polyisoprene polyols, hydrogenated polyisoprene polyols, polyurethane polyols which are reaction products of polyether polyols and polyisocyanates, and polyether adducts of polyhydric alcohols.

[Polyol component having carboxyl group]
Examples of polyols having functional groups that react with cross-linking agents include carboxyl group-containing polyols. For example, dimethylolbutanoic acid, dimethylolpropionic acid, and derivatives thereof (cacrolactone adduct, ethylene oxide adduct, propylene oxide adduct, etc.), 3-hydroxysalicylic acid, 4-hydroxysalicylic acid, 5-hydroxysalicylic acid, 2- carboxy-1,4-cyclohexanedimethanol and the like. Among them, dimethylolbutanoic acid and dimethylolpropionic acid are preferred in the present invention because they can increase the concentration of carboxyl groups in the resin.

[Polyisocyanate component]
Examples of polyisocyanate components include aromatic polyisocyanates, aliphatic polyisocyanates, araliphatic polyisocyanates, and alicyclic polyisocyanates.

Aromatic polyisocyanates include 1,3-phenylene diisocyanate, 4,4′-diphenyl diisocyanate, 1,4-phenylene diisocyanate, 4,4′-diphenylmethane diisocyanate, 2,4-tolylene diisocyanate, 2,6-tri diisocyanate, 4,4′-toluidine diisocyanate, 2,4,6-triisocyanatotoluene, 1,3,5-triisocyanatobenzene, dianisidine diisocyanate, 4,4′-diphenyl ether diisocyanate, 4,4′,4″ -triphenylmethane triisocyanate and the like.

Aliphatic polyisocyanates include trimethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate, pentamethylene diisocyanate, 1,2-propylene diisocyanate, 2,3-butylene diisocyanate, 1,3-butylene diisocyanate, dodecamethylene diisocyanate, 2, 4,4-trimethylhexamethylene diisocyanate and the like can be mentioned.

Examples of araliphatic polyisocyanates include ω,ω'-diisocyanate-1,3-dimethylbenzene, ω,ω'-diisocyanate-1,4-dimethylbenzene ω,ω'-diisocyanate-1,4-diethylbenzene, 1, 4-tetramethylxylylene diisocyanate, 1,3-tetramethylxylylene diisocyanate and the like can be mentioned.

Alicyclic polyisocyanates include 3-isocyanatomethyl-3,5,5-trimethylcyclohexyl isocyanate, 1,3-cyclopentane diisocyanate, 1,3-cyclohexane diisocyanate, 1,4-cyclohexane diisocyanate, methyl-2,4 -cyclohexane diisocyanate, methyl-2,6-cyclohexane diisocyanate, 4,4'-methylenebis(cyclohexyl isocyanate), 1,4-bis(isocyanatomethyl)cyclohexane, 1,4-bis(isocyanatomethyl)cyclohexane and the like. can.

Also, the so-called adduct obtained by adding a trifunctional alcohol such as trimethylolpropane to the above polyisocyanate, the biuret product obtained by reacting the above polyisocyanate with water, and the above polyisocyanate forming an isocyanurate ring. Ammers and the like can also be used in combination. A reaction product of the aforementioned polyhydric alcohol polyether adduct and diisocyanate can also be used as the polyisocyanate component.

As the polyisocyanate used for obtaining the urethane-based polymer, 4,4'-diphenylmethane diisocyanate, hexamethylene diisocyanate, 3-isocyanatomethyl-3,5,5-trimethylcyclohexyl isocyanate (isophorone diisocyanate) and the like are preferable.

[Polyamine component]
When obtaining a urethane-based polymer, a polyamine component can be used as necessary. Examples of polyamine components include ethylenediamine, isophoronediamine, phenylenediamine, 2,2,4-trimethylhexamethylenediamine, tolylenediamine, hydrazine, piperazine, hexamethylenediamine, propylenediamine, dicyclohexylmethane-4,4-diamine, Diamines such as 2-hydroxyethylethylenediamine, di-2-hydroxyethylethylenediamine, di-2-hydroxyethylpropylenediamine, 2-hydroxypropylethylenediamine and di-2-hydroxypropylethylenediamine can be mentioned. Isophoronediamine and 2,2,4-trimethylhexamethylenediamine are preferable because the reaction can be easily controlled and they are excellent in hygiene.
By using the polyamine component, urea bonds having higher cohesive force than urethane bonds are formed, so that a pressure-sensitive adhesive with high cohesive force can be obtained.

[Monofunctional hydroxyl group component]
The monofunctional hydroxyl group component used as one of the terminal terminating agents in obtaining the urethane-based polymer is not particularly limited, and may be methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, 1- Hexanol, 1-octanol, 2-diethylaminoethanol and the like can be mentioned, and one or more selected from these groups can be used. Among them, 2-diethylaminoethanol is preferable in that a tertiary amino group can be introduced at the terminal.

[Monofunctional Amine Component]
As with the monofunctional hydroxyl group component, the monofunctional amine component used as one of the terminal terminating agents is not particularly limited, and may be hexylamine, octylamine, diethylamine, dodecylamine, hexadecylamine, octadecylamine, stearylamine, Oleylamine, cyclohexylamine, monoethanolamine, monopropanolamine, diethanolamine, dipropanolamine and the like can be mentioned.
By using these monofunctional hydroxyl group components and/or monofunctional amine components as terminal blocking agents, the stability of the urethane polymer over time can be improved.

In the present invention, the urethane-based polymer is prepared by mixing essential components such as a polyol component, a polyisocyanate component, and a monomer serving as an introduction source of an amine oxide group into a polyamine component, a monofunctional hydroxyl group component, and a monofunctional All of the amine components of may be reacted simultaneously (one-shot method) or may be reacted sequentially. In order to reliably produce the desired urethane-based polymer as the main product, a sequential reaction in which at least one of these components is sequentially reacted is preferred. When preparing a urethane-based polymer by sequential reactions, for example, the following method can be applied.

A step of reacting a polyol component, a polyisocyanate component, and a monomer serving as a source of introduction of amine oxide groups under conditions in which the polyisocyanate component is in excess to obtain a urethane prepolymer having terminal isocyanate groups, followed by the urethane prepolymer and polyamine. component to obtain an isocyanate-terminated polyurethane polyurea, and finally reacting the remaining isocyanate groups with a monofunctional hydroxyl group component and/or a monofunctional amine component.

It should be noted that the method of proceeding with the sequential reaction is not limited to the methods exemplified above.

The urethane-based polymer of the present invention may be produced by reacting raw materials in the absence of a solvent or by reacting them in an organic solvent.
Examples of organic solvents include ketone compounds such as acetone, methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone; ester compounds such as methyl acetate, ethyl acetate, butyl acetate, ethyl lactate and methoxyethyl acetate; ethers such as diethyl ether and ethylene glycol dimethyl ether. aromatic compounds such as toluene and xylene; aliphatic compounds such as pentane and hexane; and halogenated hydrocarbon compounds such as methylene chloride, chlorobenzene and chloroform.

In addition, when synthesizing the urethane-based polymer, a catalyst can be added as necessary. 3 such as (5,4,0)undecene-7, 1,5-diazabicyclo(4,3,0)nonene-5,6-dibutylamino-1,8-diazabicyclo(5,4,0)undecene-7 Primary amines; reactive tertiary amines such as triethanolamine; these may be used alone or in combination of two or more.
The isocyanate group-containing urethane prepolymer is preferably obtained by reacting the above-mentioned polyol component, polyisocyanate component, and a monomer serving as an introduction source of amine oxide groups in an organic solvent at 120° C. or less in the presence of a catalyst. More preferably, the reaction is carried out at ~110°C for 1 to 20 hours. If the temperature is higher than 110°C, it becomes difficult to control the reaction rate, making it difficult to obtain a urethane prepolymer having a desired molecular weight and structure.
The reaction between the isocyanate group and the polyamine component is preferably carried out in an organic solvent at 60°C or less. If the temperature is higher than that, it becomes difficult to control the reaction rate, and it becomes difficult to obtain a urethane-based polymer having a predetermined molecular weight and structure.

[Oxidation]
An oxidizing agent is added to a solution containing a tertiary amino group-containing unsaturated monomer or a urethane polymer having a tertiary amino group, and the mixture is heated at 20°C to 100°C for 0.1 to 100 hours, preferably 1 to 50 hours. Tertiary amino groups can be oxidized by reacting for time.

As the oxidizing agent, an oxidizing agent such as peroxide or ozone is used.
Examples of peroxides include hydrogen peroxide, ammonium persulfate, sodium persulfate, peracetic acid, metachloroperbenzoic acid, benzoyl peroxide, t-butyl hydroperoxide, etc. Hydrogen peroxide is preferred, and is usually an aqueous solution. used in the form Although there is a difference in degree, peroxides also function as radical generators, so in the case of a vinyl polymer containing a tertiary amino group-containing unsaturated monomer (a1) as an essential raw material, oxide It is preferable to Also, in the case of a urethane-based polymer, which will be described later, it is preferable to oxidize after polymerization so as not to cause a side reaction.
Generally, the amount of the oxidizing agent used is 0.2 to 3 times the molar equivalent of the oxidizable functional group, that is, the tertiary amino group, and further 0.5 to 2 times the molar equivalent. It is more preferred to use molar equivalents.

The obtained polymer solution can also be used after treating the residual peroxide by a known method. Specific examples include reducing agent addition treatment, ion exchange treatment, activated carbon treatment, treatment with a metal catalyst, and the like.
The obtained polymer solution can be used as it is, but if necessary, the amine oxide group-containing polymer can be isolated and used by known methods such as reprecipitation and solvent distillation. In addition, the isolated amine oxide group-containing polymer can be further purified by reprecipitation, solvent washing, membrane separation, adsorption treatment, or the like, if necessary.

<Amine oxide group content>
The amine oxide groups impart biofilm formation inhibitory properties to the polymer. The amine oxide group content in the urethane-based polymer (a) is preferably 0.25-5 mmol/g, more preferably 0.5-2 mmol/g. By setting it to 0.25 to 5 mmol/g, it is possible to maintain the optimum biofilm formation suppressing ability even when immersed in water for a long time.
When the urethane-based polymer (a) is obtained by polymerizing a monomer having an amine oxide group, the amine oxide group content in the urethane-based polymer (a) is determined from the amount of the monomer having an amine oxide group used for polymerization. can ask. On the other hand, in the case of oxidizing a polymer obtained after polymerizing a monomer essentially containing a tertiary amino group-containing monomer, it can be calculated according to Equation 1 below.

<Mass average molecular weight (Mw)>
The weight average molecular weight of the urethane polymer (a) is 10,000 to 10,000,000, preferably 5,000 to 6,000,000, more preferably 10,000 to 600,000. , particularly preferably 10,000 to 100,000.
When the molecular weight is 10,000 or more, cohesive force can be imparted, peeling from the coating substrate can be suppressed, and a long-term biofilm formation suppressing effect can be exhibited. In addition, when it is 10,000,000 or less, the viscosity is appropriate, and thus the coatability is improved. Therefore, the mass-average molecular weight of the urethane-based polymer (a) is limited within the above specific range.

<Crosslinking agent>
The biofilm formation suppression coating agent of the present invention can contain a cross-linking agent. By including a cross-linking agent, when the urethane-based polymer (a) has a cross-linkable group, cross-linking can be formed in the coating film to improve water resistance.
The cross-linking agent that can be used in the present invention is preferably one that reacts with the carboxyl group contained in the urethane polymer (a) described above. In addition to those having functional groups, metal chelate compounds, carbodiimide group-containing compounds, and the like can be mentioned. These cross-linking agents can be used for the purpose of increasing the elastic modulus and resistance of the coating film, and can be used for adjusting the adhesive force.

[Crosslinking Agent Having Epoxy Group]
The epoxy group-containing cross-linking agent used in the present invention is not particularly limited as long as it has two or more epoxy groups in one molecule.
Examples of cross-linking agents having a bifunctional epoxy group include ethylene glycol diglycidyl ether, polyethylene oxide diglycidyl ether, propylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, tetramethylene glycol diglycidyl ether, and polytetramethylene glycol diglycidyl. Aliphatic epoxy compounds such as ether, 1,6-hexanediol diglycidyl ether, neopentyl glycol diglycidyl ether, polybutadiene diglycidyl ether, bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, biphenol type Aromatic epoxy compounds such as epoxy resins, dihydroxybenzophenone diglycidyl ether, resorcinol diglycidyl ether, hydroquinone diglycidyl ether, dihydroxyanthracene type epoxy resins, bisphenol fluorenediglycidyl ether, N,N-diglycidylaniline, etc. Hydrogenated products of epoxy compounds, alicyclic epoxy compounds such as diglycidyl hexahydrophthalate, and the like are included.
Examples of cross-linking agents having three or more epoxy groups include triglycidyl isocyanurate, trisphenol-type epoxy compounds, tetrakisphenol-type epoxy compounds, phenol novolac-type epoxy compounds, and the like.

[Crosslinking agent having isocyanate group]
The isocyanate group-containing cross-linking agent used in the present invention is not particularly limited as long as it is a compound having two or more isocyanate groups in one molecule.
Examples of bifunctional isocyanate compounds include 2,2′-diphenylmethane diisocyanate, 2,4′-diphenylmethane diisocyanate, 4,4′-diphenylmethane diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, hexa Examples include methylene diisocyanate and isophorone diisocyanate.
Examples of the trifunctional isocyanate compound include the trimethylolpropane adduct of the diisocyanate described above, the water-reacted biuret form, and the trimer having an isocyanurate ring.
Moreover, the isocyanate group in the cross-linking agent having an isocyanate group may be blocked or may not be blocked.
The blocked isocyanate crosslinking agent used in the present invention may be a blocked isocyanate compound in which the isocyanate group in the isocyanate compound is blocked with ε-caprolactam, MEK oxime, cyclohexanone oxime, pyrazole, phenol, or the like, and is particularly limited. not to be

[Crosslinking Agent Having Aziridinyl Group]
The aziridine compound used in the present invention is not particularly limited as long as it is a compound having two or more aziridine groups in one molecule. Examples of aziridine compounds include 2,2′-bishydroxymethylbutanol tris[3-(1-aziridinyl)propionate], 4,4-bis(ethyleneiminocarbonylamino)diphenylmethane, and the like.

[Carbodiimide group-containing compound]
As the carbodiimide group-containing compound used in the present invention, the Carbodilite series of Nisshinbo Co., Ltd. can be used, and aqueous types such as V-02, V-04, V-06, V-10, V-01 , V-03, V-05, V-07 and V-09.

[β-hydroxyalkylamide group-containing compound]
In the present invention, a compound containing a β-hydroxyalkylamide group can also be used as a cross-linking agent.
The β-hydroxyalkylamide group-containing compound is not particularly limited as long as it contains a β-hydroxyalkylamide group in the molecule. Examples of the β-hydroxyalkylamide group-containing compound include various compounds such as N,N,N',N'-tetrakis(hydroxyethyl)adipamide (PrimidXL-552 manufactured by Em Chemie).

In the present invention, the cross-linking agent may be used singly or in combination of two or more. The amount of the cross-linking agent to be used may be determined in consideration of the type and number of moles of functional groups contained in the urethane polymer (a), and is not particularly limited, but usually the urethane polymer (a) It is used in the range of 0.1 parts by mass to 100 parts by mass with respect to 100 parts by mass. By blending in a range smaller than the number of moles of the functional groups contained in the urethane-based polymer (a), it is possible to eliminate concerns about liberation of unreacted cross-linking agents. Within this range, particularly excellent performance is exhibited in each of the intended effects of suppressing biofilm formation.

<Adjustment of biofilm formation suppression coating agent>
The biofilm formation-inhibiting coating agent of the present invention preferably contains 1 to 50% by mass, more preferably 5 to 30% by mass, of the urethane-based polymer (a) in 100% by mass of the coating agent. By setting the urethane-based polymer (a) content to 1% by mass or more, the effect of suppressing biofilm formation by amine oxide groups can be exhibited. Moreover, the biofilm formation suppression coating agent of this invention may also contain components other than a urethane-type polymer (a).

<Solvent>
The biofilm formation-inhibiting coating agent of the present invention may contain a solvent as a component other than the urethane-based polymer (a), or may contain two or more of them in combination. The solvent can be appropriately selected from conventionally known solvents in consideration of the solubility of the urethane-based polymer (a), which depends on the amount of amine oxide, printing conditions, and the like.
For example, when the amount of amine oxide in the urethane polymer (a) is large, water, alcohols such as methanol and ethanol, ketones such as acetone and ethyl methyl ketone, ethers such as tetrahydrofuran and diethyl ether, methyl acetate and Esters such as ethyl acetate, dimethylsulfoxide, acetonitrile, organic acids such as formic acid and acetic acid, and organic bases such as N,N-dimethylformamide can be selected. On the other hand, when the amount of amine oxide in the urethane polymer (a) is small, ketones such as acetone and ethyl methyl ketone, ethers such as tetrahydrofuran and diethyl ether, esters such as methyl acetate and ethyl acetate, dimethyl sulfoxide, In addition to acetonitrile, halogen solvents such as dichloromethane and trichloromethane can be selected.

Furthermore, the biofilm formation suppression coating agent of the present invention may contain various additives within a range that does not impair the effects of the present invention.

<Biofilm formation suppression laminate>
The biofilm formation-inhibiting laminate of the present invention has a coating film formed of the biofilm formation-inhibiting coating agent of the present invention on a substrate.
As a method for forming a coating film, various coating film forming methods (coating/printing/drying method) can be selected according to the substrate. Examples thereof include various printing methods such as gravure and offset, as well as an inkjet method, a spray method, and an immersion method, but are not limited to these. Drying after coating is sufficient as long as the solvent can be removed, and the drying temperature can be appropriately selected from the solvent and the like contained in the biofilm formation-inhibiting coating agent. Industrially, it is desirable that the temperature is 40 to 180° C. for about 2 minutes. Furthermore, when the biofilm formation suppressing coating agent of the present invention contains a cross-linking agent, it is preferable to provide a step for promoting the cross-linking reaction. Cross-linking conditions are generally 40-150° C. for 6-24 hours, but are not limited thereto.
The thickness of the coating film made of the biofilm formation-inhibiting coating agent can be appropriately selected within a range that does not impair the effects of the present invention.

<Base material>
Since the biofilm formation suppression coating agent of the present invention can be applied to a wide range of fields where biofilm hazards are a concern, microorganisms adhere to medical equipment, manufacturing equipment, or the inner surface of water tanks, etc., and biofilms are formed. It can be suitably used on the surface of a substance that is assumed to be used. Therefore, as the substrate, any substrate that has been conventionally used for the above applications can be used without limitation, and examples thereof include substrates made of materials such as plastics, glass, ceramics, and metals.

The present invention will be specifically described by the following examples, but the following examples are not intended to limit the scope of rights of the present invention. In addition, "parts" and "%" in the examples represent "mass parts" and "mass%".

<Method for measuring mass average molecular weight (Mw)>
The weight average molecular weight of the urethane-based polymer (a) was measured by gel permeation chromatography (GPC) in terms of standard polystyrene. The measurement apparatus and measurement conditions were based on condition 1 below, and condition 2 was selected depending on the solubility of the sample and the like. However, depending on the type of polymer, a more appropriate carrier (eluent) and a column compatible with it were selected. Other matters were based on JISK7252-1 to 4:2008. For poorly soluble polymer compounds, measurements were made at a soluble concentration under the following conditions.
Moreover, when the molecular weight measurement of the urethane-based polymer (a) is difficult, the weight-average molecular weight of the amine oxide precursor polymer was used as the weight-average molecular weight of the urethane-based polymer (a). The mass-average molecular weight of the amine oxide precursor polymer employs a value measured by gel permeation chromatography (GPC) in terms of standard polystyrene.
(Condition 1)
Column: TOSOHTSKgelSuperHZM-H,
A combination of TOSOHTSKgelSuperHZ4000 and TOSOHTSKgelSuperHZ10,000.
Carrier: Tetrahydrofuran Measuring temperature: 40°C
Carrier flow rate: 1.0 mL/min
Sample concentration: 0.1% by mass
Detector: RI (refractive index) detector Injection volume: 0.1 mL
(Condition 2)
Column: Two columns of TOSOHTSKgelSuperAWM-H are connected.
Carrier: 10 mM LiBr/N-methylpyrrolidone Measurement temperature: 40°C
Carrier flow rate: 1.0 mL/min
Sample concentration: 0.1% by mass
Detector: RI (refractive index) detector Injection volume: 0.1 mL
(Condition 3)
Column: TOSOH TSKgel Super AW4000,
A combination of TOSOHTSKgelSuperAW3000 and TOSOHTSKgelSuperAW2500.
Carrier: N,N-dimethylformamide (1 L), triethylamine (3.04 g), LiBr (0.87 g) mixed liquid Measurement temperature: 40 ° C.
Carrier flow rate: 0.6 mL/min

<Method for measuring acid value>
The acid value is expressed in mmol of potassium hydroxide required to neutralize acid groups contained in 1 g of resin, and may be measured by a known method, generally according to JIS K0070. The method is shown below.
Accurately weigh 0.5 to 2 g of the sample (solid content: Sg). 10 mL of neutral ethanol is added to the precisely weighed sample to dissolve it. The obtained solution is subjected to potentiometric titration with 0.1 mol/l ethanolic potassium hydroxide solution (titer: F). The point at which the potential difference curve reached a maximum was defined as the end point, and the titration amount (AmL) at this time was used to determine the acid value by the following (Equation 2).
(Formula 2) Acid value (mmol/g) = (A x F x 0.1)/S

<Method for measuring amine value>
The amine number is the equivalent of hydrochloric acid in mmol of potassium hydroxide required to neutralize the amino groups contained in 1 g of resin. The amine value was measured by the following method.
Accurately weigh 0.5 to 2 g of the sample (solid content: Sg). 10 mL of neutral ethanol is added to the precisely weighed sample to dissolve it. The resulting solution is subjected to potentiometric titration with a 0.1 mol/l ethanolic hydrochloric acid solution (titer: f). The point at which the potential difference curve reached a maximum was defined as the end point, and the titration amount (AmL) at this time was used to determine the amine value according to the following (Equation 3).
(Formula 3) Amine value (mmol/g) = (A x f x 0.1)/S

<Synthesis of urethane-based polymer (a) containing amine oxide group>
(Production example 1)
A four-necked flask equipped with a stirrer, a reflux condenser, a nitrogen inlet tube, an inlet tube, and a thermometer was charged with 4.75 parts of N-methyldiethanolamine as a tertiary amino group-containing diol and P2011 (Kuraray Polyol P2011 (Kuraray Polyol P2011) as a polyol component. 130.10 parts of polyester polyol (manufactured by Kuraray Co., Ltd., hydroxyl value 56.1) and 19.6 parts of hexamethylene diisocyanate as a polyisocyanate component were charged, and the mixture was heated to 60°C while stirring under a stream of nitrogen to dissolve uniformly. Subsequently, 0.002 part of dibutyltin dilaurate was added as a catalyst to this and reacted at 110° C. for 3 hours.
After that, the temperature was lowered to 40° C., and 0.60 part of isophoronediamine was added dropwise as a polyamine component to carry out a chain extension reaction. Furthermore, 1.65 parts of diethylethanolamine was added as a terminal terminator and reacted at 40° C. for 30 minutes to obtain a solution of an amine oxide precursor polymer, that is, a polymer having a tertiary amino group.
Next, 3.91 parts of 35% aqueous hydrogen peroxide as an oxidizing agent (an amount equimolar to the tertiary amino group) was added to the resulting solution of the polymer having a tertiary amino group, and the mixture was reacted at 70°C for 16 hours. Oxidation of the amino group was carried out by After confirming that the amine oxide conversion rate exceeded 98%, it was cooled and taken out, and then the solvent was completely volatilized in an oven to obtain a urethane polymer (a).
The amine oxide group content of the obtained polymer was 0.26 mmol/g.
Moreover, the mass average molecular weight of the obtained urethane-based polymer (a) was 15,200.

(Production Examples 2-6) (Comparative Production Examples 1-2)
In the same manner as in Production Example 1, synthesis was carried out according to the composition and charged mass parts shown in Table 1 to synthesize polymers (Production Examples 2-6) (Comparative Production Examples 1-2).

Table 1 shows the characteristic values of the obtained urethane-based polymer.

Abbreviations in Table 1 are shown below.
MDEA: N-methyldiethanolamine
DMAP: 3-dimethylaminopropane-1,2-diol
DMBA: dimethylolbutanoic acid
P2011: Kuraray polyol P2011 (polyester polyol, manufactured by Kuraray Co., Ltd., hydroxyl value 56.1)
PEG#2000: PEG#2000 (polyethylene glycol, manufactured by NOF Corporation, molecular weight 2,000)
D2000: Uniol D2000 (polypropylene glycol, manufactured by NOF Corporation, molecular weight 2,000)
HDI: Hexamethylene diisocyanate
IPDI: isophorone diisocyanate
IPDA: isophorone diamine
DEEA: Diethylethanolamine
HPO: 35% hydrogen peroxide solution

<Adjustment of biofilm formation suppression coating agent>
[Example 1]
(Biofilm formation suppression coating agent 1)
10.0 parts of the resulting amine oxide group-containing polymer (manufacturing example 1) was diluted with 90.0 parts of ethanol to prepare a 10% coating solution, and a biofilm formation-inhibiting coating agent 1 was obtained.

[Examples 2-10, Comparative Examples 1-2]
(Biofilm formation suppression coating agents 2 to 12)
In the same manner as in Example 1, biofilm formation suppression coating agents 2 to 12 were prepared with the composition and charged mass parts shown in Table 2.

Abbreviations in Table 2 are shown below.
ALCH: Aluminum chelate compound manufactured by Kawaken Fine Chemicals Co., Ltd.
PZ33: Polyfunctional aziridine compound manufactured by Nippon Shokubai Co., Ltd.
V02: Aqueous carbodiimide group-containing compound manufactured by Nisshinbo Inc.
EX321L: Polyfunctional aliphatic epoxy compound manufactured by Nagase ChemteX Corporation
XL552: Hydroxyalkylamide group-containing compound manufactured by M Chemie Co., Ltd.
EtOH: ethanol
EtOAc: ethyl acetate

<Evaluation of biofilm formation inhibitor coating agent>
The biofilm formation-inhibiting coating agents (coating liquids) obtained in Examples and Comparative Examples were evaluated as follows. Table 3 shows the results.

[water resistant]
2.0 g of the resulting coating agent 1-12 was added to a precisely weighed shallow metal container and dried by heating at 150° C. for 10 minutes. After taking out from the oven and precisely weighing together with the shallow metal container, 5.0 g of ion-exchanged water was added to the shallow metal container and allowed to stand overnight. After the ion-exchanged water was sucked out from the shallow metal container, it was again dried at 150° C. for 10 minutes, and the shallow metal container was precisely weighed. The solubility in water was calculated by the following formula, and the water resistance was evaluated based on the four-level evaluation criteria.
Water solubility (%) = 100-[(zx)/(yx)] x 100
x: mass of shallow metal container (g)
y: Mass (g) before treatment with ion-exchanged water
z: Mass (g) after treatment with ion-exchanged water
◎: water solubility ≤ 2%: very good ○: 2% < water solubility ≤ 4%: good △: 4% < water solubility ≤ 10%: usable ×: 10% < water solubility Solubility: not available

<Production and evaluation of biofilm formation suppressing laminate>
Each of the obtained coating agents 1-12 was coated on a 75 μm thick polyethylene terephthalate (PET) film (manufactured by Panac Co., Ltd.; Lumirror #75, surface ozone-treated) and coated with a bar so that the film thickness after drying was 1.0 μm. After coating with a coater and drying at 80° C. for 2 minutes, it was heated at 80° C. for 24 hours to obtain a laminate 1-12. Separately, Staphylococcus aureus (ATCC 25923) was pre-incubated for 24 hours at 37° C. and grown. The bacterial solution was added to phosphate buffered water (PBW) to prepare a 1% bacterial solution.
The resulting laminate was cut into a size of 1.5 cm x 1.5 cm, and placed in each well of a 24-well microplate (manufactured by Falcon) so that the coated surface faces upward. 0 mL was added and immersed at 37° C. for 24 hours.
Then, 1.0 mL of sterilized water was removed from the 24-well microplate, 1.0 mL of separately prepared Staphylococcus aureus solution was added, and cultured at 25° C. for 24 hours or 25° C. for 168 hours. After culturing for 24 hours or 168 hours, remove the bacterial solution, wash the coating film with 1.2 mL of sterile water three times, add 0.1% crystal violet aqueous solution (manufactured by Wako Pure Chemical Industries, Ltd.), and continue for 20 minutes. The biofilm was stained on standing. Then, it was washed with 1.2 mL of sterilized water three times and air-dried to obtain a biofilm-stained laminate.
Crystal violet was extracted from the stained laminate using 2.0 mL of a 33% acetic acid solution, and the absorbance of the extract was measured using a microplate reader.
The biofilm formation inhibitory property was evaluated from the absorbance according to the following four stages of evaluation criteria. Table 3 shows the results.
◎: absorbance ≤ 0.10: very good ○: 0.10 < absorbance ≤ 0.13: good △: 0.13 < absorbance ≤ 0.20: usable ×: 0.20 < absorbance: not usable

From Table 3, since the polymer used in Comparative Example 1 had a low concentration of amine oxide groups, the biofilm formation inhibitory properties after 24 hours and 168 hours of culture were poor. The polymer used in Comparative Example 2 had a low molecular weight, and the coated polymer was peeled off, so the biofilm formation suppression property after 24 hours of culture was poor.

On the other hand, the biofilm formation suppressing coating agent containing the urethane-based polymer (a) having an amine oxide group and a mass average molecular weight of 10,000 to 10,000,000 has excellent water resistance and long-term It was confirmed that it showed an excellent effect in biofilm formation suppression performance.
In particular, when the amine oxide group content in the urethane-based polymer (a) is 0.25 to 5 mmol/g, it was confirmed that the optimal biofilm formation suppression ability is maintained even when immersed in water for a long time. . In addition, it was shown that when a polyol component having a carboxyl group was used, excellent water resistance and long-term biofilm formation suppression ability were obtained.

Claims (5)

A biofilm formation-inhibiting coating agent comprising a urethane-based polymer (a) containing an amine oxide group and having a mass average molecular weight of 10,000 to 10,000,000. The biofilm formation-inhibiting coating agent according to claim 1, wherein the urethane-based polymer (a) contains 0.25 to 5 mmol/g of amine oxide groups. The biofilm formation inhibitory coating agent according to claim 1 or 2 , wherein the urethane polymer (a) has at least one structure represented by the following general formulas 1 to 3.

(In the formula,
R ¹ , R ³ and R ⁶ each independently represent an alkylene group having 1 to 6 carbon atoms,
R ² , R ⁴ , R ⁵ , R ⁷ and R ⁸ are an alkyl group, an aryl group, an aralkyl group and a pyridyl group;
Y represents O or NH,
** represents the bonding position with the main chain of the urethane-based polymer. ) The biofilm formation inhibiting coating agent according to any one of claims 1 to 3 , further comprising a cross-linking agent. A biofilm formation-inhibiting laminate having a coating film comprising the biofilm formation-inhibiting coating agent according to any one of claims 1 to 4 on a substrate.